Anserobilharzia brantae, Brant, Sara V., Jouet, Damien, Ferte, Hubert & Loker, Eric S., 2013

Brant, Sara V., Jouet, Damien, Ferte, Hubert & Loker, Eric S., 2013, Anserobilharzia gen. n. (Digenea, Schistosomatidae) and redescription of A. brantae (Farr & Blankemeyer, 1956) comb. n. (syn. Trichobilharzia brantae), a parasite of geese (Anseriformes), Zootaxa 3670 (2), pp. 193-206 : 195

Anserobilharzia brantae n. gen., comb n.

( Figs. 1–2 ; Tables 1–2)

Type host: Branta canadensis Linnaeus.

Other hosts. Anser anser Linnaeus , Chen caerulescens Linnaeus , Branta bernicla Linnaeus.

Intermediate hosts. Gyraulus parvus (Say) .

Type locality. Mattamuskeet National Wildlife Refuge, North Carolina ( Farr & Blankemeyer 1956).

Other localities. Churchill, Manitoba, Canada; Shady Lakes, Albuquerque, New Mexico; Prospect Lake, Colorado Springs, Colorado; ( Brant and Loker 2009b). Der-Chantecoq Lake, France ( Jouet et al. 2009).

Type material. U. S. National Parasite Collection Holotype USNPC # 047607, Allotype USNPC # 047608.

Material examined and/or deposited. Paratypes USNPC # 047609, other vouchers USNPC #’s 029719.02, 058095, 088769. Division of Parasitology, Museum of Southwestern Biology, University of New Mexico – MSB Para 176, MSB Para 182, MSB Para 184, MSB Para 7984, MSB Para 7985, MSB Para 14739–14742. Other specimens that were not examined are at the National Museum of Canada Invertebrate Collection, Ottawa, Ontario Accession No. NMCP 1985–0063, 0064.

Deposition of the nucleotide sequences from this paper. Sequences deposited in GenBank under accession numbers KC839984 – KC839985 and KC570945 – KC570956 .

Site of infection. Mesenteric veins of large intestine and posterior small intestine.

Description. Males ( Fig. 1 , Table 2): Gynaecophoric canal short and shallow with a relatively non-muscular anterior portion and muscular, spined posterior third portion. Genital papillae near anterior margin within gynaecophoric canal. Seminal vesicle located between ventral sucker and gynaecophoric canal, and divided into external and internal seminal vesicle. Caecal reunion anteriad to elongate, sac-like seminal vesicle. Common caecum spiraling among testes. Testes numerous, commencing a short distance from the posterior gynaecophoric canal and extending all the way in to the posterior end of the worm.

Females ( Fig. 1 ; Table 2): Caecal reunion just caudad to the seminal receptacle region. Common caecum spiraling among the vitellaria. Seminal receptacle caudad to ovary. Ovary convoluted and sac-like in anterior half of body. Vitelline follicles rounded or irregular in shape originating caudad to the seminal receptacle. Uterus opening immediately posterior to ventral sucker.

Eggs ( Fig. 2 ; Table 2): In feces, smooth-shelled, ovoid, with a small, recurved terminal spine. From the adult females examined, only one egg was present in the short uterus. New egg measurements from this study: from the host intestine of: Branta canadensis were 75–90 x 41 –83µm and from the host intestine of Anser anser were 67– 119 x 42 –87µm.

Cercariae ( Fig. 2 ; Table 2): Brevifurcate apharyngeate distomes. Body short relative to tail. Body spinose but fewer to no spines on posterior body, spines longer on head organ. Head organ large and muscular. Eyespots composed of small pigmented granules. Excretory system with five pairs of flame cells in body and one pair at top of tail stem. Tail densely spinose at base with supination lessening towards furcae. Furcae are sparsely spinose, each bearing fin-folds along entire length. The cercariae are active swimmers within the water column. On emergence from the snail, they tend to accumulate on the side of the container with the highest concentration of light. They rest attached to substrate by ventral sucker, with anterior portion of body flexed dorsally with the tail perpendicular.

Figures

FIGURE 1. Anserobilharzia brantae comb. n. (a) anterior and posterior end of a female; (b) anterior and posterior end of a male. A, acetabulum; CB, caecal bifurcation; CG, canalis gynaecophorus; CR, caecal reunion; GO, genital opening; GP, Genital papilla; I, intestine; O, ovary; OE, esophagus; OS, oral sucker; RS, receptaculum seminis; T, testes; U, uterus; VI, vitellaria; VSE, vesicula seminalis externa; VSI, vesicula seminalis interna.

FIGURE 2. Image of Anserobilhazia brantae eggs, cercariae and snail intermediate host: A) egg from North American Chen caerulescens taken from a scraping of the large intestine, scale bar 42 μm; B) egg from European Anser anser taken from feces; C) snail intermediate host Gyraulus parvus. Shell diameter = 5 mm; D) adults from large intestinal vein of C. caerulescens; E) cercaria collected from G. parvus, scale bar = 320 μm. F and G) eggs in intestinal mucosa from Anser anser.